Sociolinguistics ; History of language ; Language change ; Grammatisierung; Grammaticization; Kreolisierung; Creolization; Subjektivierung; Subjectification; Grammaticalization ; Determinologisation ; Language diffusion; Language shift; Sprachwechsel; Language spread ; Sprachentod; Extinct language; Language endangerment; Bedrohte Sprache; Linguicide; Linguizid; Language death ; English